Common heat exchangers are used to control the temperature of fluids, in particular of gases. Such heat exchangers make it possible hereby to heat and/or to cool the fluid. Such heat exchangers can have temperature-control elements for this purpose.
It is known to provide electrically dissipative heating elements, as such temperature-control elements, which generate dissipative heat when flowing through an electric current. Such a heating element is known from WO 92/06570 A. The heating element is hereby embodied as a PTC resistor or a positive temperature coefficient heating element (PTC heating element) and is used to heat an air flow.
The disadvantage of such dissipative heating elements is that they do not allow for a sufficient heating and/or that the resource consumption thereof is too high, in particular when only few electrical resources are available.
It is also known from the prior art to use thermoelectric temperature-control elements to control the temperature of a fluid. The use of such a thermoelectric heating element in a heat exchanger is known from DE 10 2009 058 673 A1 and from EP 2 518 424 A1. A Peltier element, which, due to a corresponding switching and application of an electrical voltage, has a cold side and a warm side, is hereby used in each case. In addition to the heat transfer between the fluid and another fluid caused by the temperature difference, a corresponding arrangement of the Peltier element makes it possible to realize a heat transfer, which is achieved by means of the Peltier element, so that the total heat transfer is increased. Such Peltier elements have a plurality of differently doped semiconductors, which are interconnected with one another. To avoid a short-circuit between the semiconductors, the semiconductors are electrically insulated on both sides by means of an electrically insulating coating and/or an electrically insulating plate. Such an electrical insulation thereby routinely represents a thermal barrier, which impairs a thermal replacement of the Peltier element. Due to the fact that the electrical insulations are further arranged on the sides of the Peltier element, which are located opposite one another in the heat flow direction, the heat exchange between the Peltier element and the fluid or object, the temperature of which is to be controlled, is made more difficult.
Such Peltier elements are moreover embodied rigidly. During operation of the Peltier element, a temperature difference inside the Peltier element occurs, which leads to thermal stresses inside the Peltier element. These thermal stresses can thereby lead to damages to the electrical insulation of the Peltier element, and to damages to the electrical connections between the semiconductors, which can negatively impact the function of the Peltier element, can in particular lead to the failure of the Peltier element.